Highest Air Pollution Tolerance Index Research Articles

Identification of urban street trees for green belt development for optimizing pollution mitigation in Delhi, India.

The current study evaluated the effects of air pollution on selected street trees in the National Capital Territory during the pre- and post-monsoon seasons to identify the optimally suitable tree for green belt development in Delhi. The identification was performed by measuring the air pollution tolerance index (APTI), anticipated performance index (API), dust-capturing capacity (DCC) and proline content on the trees. The APTI of street trees of Delhi varied significantly among different tree species (F11,88.91 = 47.18, p < 0.05), experimental sites (F3,12.52 = 6.65, p < 0.001) and between seasons (F1,31.12 = 16.51, p < 0.001), emphasizing the relationships between trees and other types of variables such as the climate and level of pollution, among other factors. This variability emphasizes the need to choose trees to use for urban greening in the improvement of air quality in different environments within cities. Ascorbic acid (AA) concentration and relative water content (RWC) had a strong influence on APTI with an extremely significant moderate positive correlation between AA concentration and APTI (r = 0.65, p < 0.001) along with RWC and APTI (r = 0.52, p < 0.001), indicating that higher levels of AA concentration and RWC are linked to increased air pollution tolerance. The PCA bi-plot indicates AA has poor positive loading coefficients with PC1 explaining 29.49% of the total variance in the dataset. The highest APTI was recorded in Azadirachta indica (22.01), Leucaena leucocephala (20.65), Morus alba (20.62), Ficus religiosa (20.61) and Ficus benghalensis (19.61), irrespective of sites and seasons. Similarly, based on API grading, F. religiosa and F. benghalensis were identified as excellent API grade 6 (81-90%), A. indica and Alstonia scholaris as very good API grade 5 (71-80%), M. alba, Pongamia pinnata and Monoon longifolium as good API grade 4 (61-70%) and Plumeria alba as moderate API grade 3 (51-60%) in different streets of Delhi. As these plants are indigenous to the region and hold significant socio-economic and aesthetic significance in Indian societies, they are advisable for avenue plantations as part of various government initiatives to support environmental sustainability.

Detect urban trees air pollution sensitivity & tolerance by leaf trait analysis in the industrial zone of Kumaun Himalaya Uttarakhand India

The plant absorbs gases and particulate matter through its leaves and contributes to cleaning the atmospheric pollutants. Sensitive plant species act as bioindicators of air pollution, while tolerant species are sinks of air pollutants. However, in ecologically sensitive regions like the Himalayas, there are no guiding rules for the selection of roadside plants for urban development due to a lack of scientific research. To address this, this study aimed to identify roadside plant species sensitivity and tolerance to air pollution near the industrial hub Rudrapur located in Kumaun Himalaya using the Air Pollution Tolerance Index (APTI). The APTI is used as a tool for evaluating and categorizing plants according to their levels of tolerance or sensitivity to air pollutants. In this study, the APTI of five plant species has been measured. A One-Way ANOVA was conducted to assess variations in biochemical parameters of five chosen roadside plant species situated at two distinct sites. Mangifera indica and Nerium species were recorded with high APTI values, indicating their tolerance to air pollution. However, the Eucalyptus species was identified as the most sensitive species with low APTI. Selecting suitable tree species to combat air pollution can improve the urban environment.

Selection of tropical trees and shrubs for urban greening in coal mine complex: a case study of Singrauli, Madhya Pradesh.

An experimental investigation was conducted to determine the effectiveness of roadside trees for removing dust and the effects of dust load on the physiology and micromorphology of the foliage. The present study was conducted near an open coal mining complex situated in Singrauli, Madhya Pradesh, India, to assess the air pollution tolerance index (APTI), anticipated performance index (API), dust capturing capacity (DCC), and leaf morphology of trees and shrubs growing around the coal fields. Results showed that Azadirachta indica, Mangifera indica, Ficus religiosa, Ailanthus excelsa, and Ficus benghalensis were the most tolerant species towards air pollution (high APTI scores), while plants like Calotropis gigantea, Lantana camara, and Tectona grandis were proven to be bio-indicator species. Butea monosperma, Ficus benghalensis, Alstonia scholaris, and Terminalia arjuna were plant species with the highest DCC. Two-way ANOVA showed significant differences site-wise and season-wise in the biochemical parameters of APTI and a considerable difference site-wise with respect to dust capturing capacity. Correlation and regression analyses revealed a very high positive correlation between APTI and ascorbic acid value. The study recommends suitable plant species to manage rising air pollution in the coal mine and nearby areas apart from suggesting the development of a green belt.

Roadside Automobile Stressed Plants as Bioindicator Based on Air Pollution Tolerance Index in Dhaka, Bangladesh

The evaluation of plants' ability to resist pollution was conducted by studying two distinct plant species, Swietenia mahagonia and Polyalthia longifolia, obtained near the urban roadsides in Dhaka during the winter season. The air pollution tolerance index (APTI) was assessed for both Polyalthia longifolia and Swietenia mahagoni. Between the two species, Polyalthia longifolia exhibited the highest air pollution tolerance index (APTI 12.54), indicating its lower sensitivity towards pollution. On the other hand, Swietenia mahagoni (APTI 12.27) demonstrated a comparatively higher sensitivity to pollutants. Polyalthia longifolia had the highest total chlorophyll concentration (TCC) (1.080 mg/g), relative water content (RWC) (88.50%), pH value (6.73), ascorbic acid concentration (ACC) (4.303). On the other hand, Swietenia mahagoni showed the lowest scores across almost all the indicators (except ACC: 5.44), demonstrating the most pollutant-sensitive species. The assessment of plants in relation to their capacity to withstand air pollution is crucial due to their role as a pollution sink. Consequently, planting species that exhibit tolerance to pollution in contaminated regions can provide several environmental advantages. Biodivers. Conserv. Bioresour. Manag. 2023, 9(2): 1-10

Identifying pollution scavenging potential of perennial plants growing in Maitreyi College Campus, University of Delhi

Aim: Air Pollution Tolerance Index (APTI) represents the potential of a plant to combat air pollution. In the present study, APTI value of 77 perennials growing in the Maitreyi College Campus, New Delhi was calculated, and these plants were classified into tolerant and sensitive species. Methodology: APTI was calculated by assessing four physiological and biochemical parameters, pH, Relative Water Content (RWC), Total Chlorophyll (TCh), and Ascorbic Acid (AA). Results: The highest APTI was observed in Musa sp. (10.52) indicating it to be the most tolerant, while the lowest in Aegle marmelos (1.93), showing it to be the most sensitive for pollution. Results showed Musa sp., Salmelia sp., Terminalia arjuna, Murraya exotica, Hamelia patens, Ravenala madagascariensis, Ficus racemosa, Cascabela thevetia, Eugenia uniflora, Nyctanthes arbortristis to have good potential in reducing air pollution in a sustainable manner. Species such as Aegle marmelos, Plumeria rubra, Dracaena, Carissa carandas, Eucalyptus sp. were sensitive to air pollution. Interpretation: Analysis of results suggested the importance of APTI analysis in a campus for cataloging the pollution tolerant and sensitive plants. The pollution tolerant plants could be used for the green belt formation, while plants, which are sensitive to pollution can be used as an indicator of pollution. Moreover, mapping and compilation of information of trees (deciduous and evergreen) and shrubs growing in the campus helped in documenting the rich flora of the campus with pollution tolerance potential. Key words: Air Pollution, Air Pollution Tolerance Index, Air quality, Trees

Comparative Study of The Physiological Condition of Six Tree Species to Air Pollution in Depok City, West Java

Background: Air pollution is a threat to the environment. Sources of air pollutants in urban environments can be in the form of dust, heavy metals, and hydrocarbons. Plants can help clean air pollutants from the atmosphere by absorption through the stomata, accumulating them, or by adsorption on the leaf surface. The Air Pollution Tolerance Index (APTI) is used as an evaluation benchmark for the Physiological conditions of plants exposed to air pollution. This research aims to study the physiological conditions of six tree species in air conditions in the Depok City area and to assess the plants' tolerance level based on the APTI calculation. Methods: The physiological parameters measured to calculate APTI were ascorbic acid, total chlorophyll, leaf extract pH, and Relative Water Content (RWC). The six tree species used as objects in this study were Artocarpus altilis, Artocarpus heterophyllus, Bauhinia purpurea, Ficus septica, Filicium decipiens, and Nephelium lappaceum. Results: Differences in the physiological conditions of six tree species in the Depok City area based on the average ascorbic acid values, total chlorophyll, leaf extract pH, and RWC. In addition, there are also differences in APTI parameters between the two research locations. Conclusions: Filicium decipiens is the plant species with the highest APTI, while Artocarpus heterophyllus has the lowest. Based on the APTI scores, Bauhinia purpurea, Ficus septica, Filicium decipiens, Nephelium lappaceum belong to moderately tolerant category, Artocarpus altilis belongs to an intermediate category, Artocarpus heterophyllus belongs to sensitive category.

Evaluation of plant species for air pollution tolerance and phytoremediation potential in proximity to a coal thermal power station: implications for smart green cities.

In metropolitan areas, air pollution poses a significant threat, and it is crucial to carefully select plant species that can tolerate such conditions. This requires a scientific approach based on systematic evaluation before recommending them to executive bodies. This study aimed to determine the air pollution tolerance index (APTI), dust retention capacity, and phytoremediation ability of 10 plant species growing in and around a lignite-based coal thermal power station. The results showed that Ficus benghalensis L. had the highest APTI, followed by Mimusops elengi L., Ficus religiosa L., Azadirachta indica A. Juss., and Annona reticulata L. F. benghalensis also showed the highest pH of leaf extract, relative water content, total chlorophyll, and ascorbic acid content, as well as the highest dust capturing capacity. Among the ten plant species, F. benghalensis, M. elengi, F. religiosa, A. indica and F. racemosa were identified as a tolerant group that can be used for particulate matter suppression and heavy metal stabilization in and around thermal power plants. These findings can inform the selection of plants for effective green infrastructure in smart green cities, promoting the health and well-being of urban populations. This research is relevant to urban planners, policymakers, and environmentalists interested in sustainable urban development and air pollution mitigation.

The importance of plant growth-promoting rhizobacteria to increase air pollution tolerance index (APTI) in the plants of green belt to control dust hazards.

Dust causes adverse effects on the physiological and biochemical characteristics of plants and limits their use in the development of the green belt. Air Pollution Tolerance Index (APTI) is an important tool to screen out plants, based on their tolerance or sensitivity level to different air pollutants. The aim of this study was to investigate the effect of two plant growth-promoting bacterial strains (Zhihengliuella halotolerans SB and Bacillus pumilus HR) and their combination as a biological solution on APTI of three desert plant species of Seidlitzia rosmarinus, Haloxylon aphyllum and Nitraria schoberi under dust stress (0 and 1.5 g m-2 30 days-1). Dust caused a significant decrease of 21% and 19%, respectively, in the total chlorophyll of N. schoberi and S. rosmarinus, an 8% decrease in leaf relative water content, a 7% decrease in the APTI of N. schoberi, and a decrease of 26 and 17% in protein content of H. aphyllum and N. schoberi, respectively. However, Z. halotolerans SB increased the amount of total chlorophyll in H. aphyllum and S. rosmarinus by 236% and 21%, respectively, and the amount of ascorbic acid by 75% and 67% in H. aphyllum and N. schoberi, respectively. B. pumilus HR also increased the leaf relative water content in H. aphyllum and N. schoberi by 10% and 15%, respectively. The inoculation with B. pumilus HR, Z. halotolerans SB and the combination of these two isolates decreased the activity of peroxidase by 70%, 51%, and 36%, respectively, in N. schoberi, and 62%, 89%, and 25% in S. rosmarinus, respectively. These bacterial strains also increased the concentration of protein in all three desert plants. Under dust stress, H. aphyllum had a higher APTI than the other two species. Z. halotolerans SB, which had been isolated from S. rosmarinus, was more effective than B. pumilus HR in alleviating the effects of dust stress on this plant. Therefore, it was concluded that plant growth-promoting rhizobacteria can be effective at improving the mechanisms of plant tolerance to air pollution in the green belt.

Health assessment of industrial ecosystems of Isfahan (Iran) using phytomonitoring: Chemometric, micromorphology, phytoremediation, air pollution tolerance and anticipated performance indices

The present study evaluated the air pollution tolerance index (APTI), anticipated performance index (API), enrichment factor (EF), pollution load index (PLI), bioaccumulation coefficient (BAC), and metal accumulation index (MAI) in grown plants of industrial ecosystems of Najafabad County near the Isfahan megacity (Iran). The existence of major, minor and trace mineral elements, physiological (pH of leaf extract and relative water content) and biochemical (proline, reducing sugar, ascorbic acid, and total chlorophyll content) factors in Clerics siliquastrum, Melia azedarach, Caesalpinia gilliesii, Eucalyptus camaldulensis, Robinia pseudoacacia, and Morus alba were evaluated to assess their suitability for phytoremediation and/or phytomonitoring. The results showed that M. azedarach and E. camaldulensis had higher APTI and API values and were categorized in the tolerant plant group. The most important factors influencing the APTI of R. pseudoacacia, E. camaldulensis, C. gilliesii, M. azedarach, C. siliquastrum and M. alba were ascorbic acid (88.1%), the pH of leaf extract (45.7%), ascorbic acid (78.9%), the pH of leaf extract (98.8%), the total chlorophyll content (56.1%), and the relative water content (54.6%), respectively. Proline showed a strong and negative correlation with the APTI (r = −0.72). Reducing sugar showed a moderate and negative correlation with the total chlorophyll (r = −0.63). The PLI showed a high pollution load for all species, especially M. azedarach. The highest values of EF, BAC, and MAI were obtained in C. siliquastrum (117.46), R. pseudoacacia (417.79), and M. azedarach (8.92), respectively. Based on the overall results of this study, it is recommended that M. azedarach be used as a tolerant species for green space development and C. siliquastrum and R. pseudoacacia as both passive bio-monitors and bio-mitigators in industrial ecosystems.

Organic Wastes Augment the Eco-Restoration Potential of Bamboo Species on Fly Ash-Degraded Land: A Field Study

Rapid industrialization has been a major cause of land degradation and other environmental problems globally. Most energy inputs in industries depend on coal-burning power stations which release various pollutants into the environment. Among these pollutants, fly ash is a concerning pollutant for soil quality, as it occupies a voluminous area of land in India and renders it unproductive. Therefore, this work attempts to evaluate the organic amendment-facilitated bioremediation/phytoremediation of fly ash-degraded land through bamboo plantations under field conditions. Three species of bamboo, Bambusa balcooa, B. tulda, and B. bambos, were planted on fly ash dumpsite soil amended with a combined dose of pressmud and farmyard manure. Results demonstrate that after two years of plantation, all the physicochemical attributes of the degraded land were improved considerably compared to the initial observations. Although all the bamboo species exhibited promising phytoremediation potential, variations were observed in their phytoremediation mechanisms: B. balcooa was the most ideal phytostabilizer species for Cu, Zn, and Ni. B. bambos was found as an ideal phytostabilizer of Pb and Zn while B. tulda was found as a phytoextractor of Cr and Zn. Additionally, all the bamboo species sequestrated atmospheric CO2 considerably, resulting in overall environmental restoration of the degraded area; B. balcooa was the most ideal species. Moreover, B. balcooa exhibited the highest air pollution tolerance index compared to other species. This study, therefore, recommends that a comprehensive analysis of organic matter-mediated phytoremediation would assist environmental managers to formulate sustainable eco-restoration strategies, ensuring a sustainable solution to land degradation.

Air Pollution Tolerance Index and Heavy Metals Accumulation of Tree Species for Sustainable Environmental Management in Megacity of Lahore

Urban air and soil quality has been deteriorating during the past few years due to urbanization, industrialization and increased number of vehicles. The goal of the current study was to assess the Air Pollution Tolerance Index (APTI) and heavy metal absorption (Pb, Cd, Zn, and Ni) potential by ten selected trees planted along the roadside in the metropolitan city of Lahore, Pakistan. APTI was estimated on the basis of biochemical parameters (chlorophyll content, ascorbic acid, pH and relative water contents) of plant extract, while heavy metals (HMs) accumulation potential was measured by a digestion method. The highest APTI was estimated in P. longifolia (78.9), followed by A. scholarils (75.9) and M. indica (71.9). Overall, these three species have significant closeness among the higher pollution-tolerance results. The poor APTI result was determined in F. religiosa (19.5) and E. citriodora (14.9). The highest Pb contents were observed in P. longifolia and M. indica i.e., 135 and 132 mg/kg, respectively. Similarly, the highest Zn contents were found in P. longifolia and S. cumini with 130 and 132 mg/kg, respectively. The Ni concentration was observed highest in P. longifolia (34 mg/kg), but in the remaining species, it is almost the same trend of Ni accumulation. Combining these trees can be useful for fostering green-belt growth along roadsides to reduce air and soil pollution and achieve environmental sustainability. But unfortunately, these species are not planted well across the roadside as they have very little biodiversity index, as compared to other species. These species should be planted in urban areas to enhance biodiversity in the urban ecosystem and make them sustainable cities and communities.

Estimation of air pollution tolerance and anticipated performance index of roadside plants along the national highway in a tropical urban city.

One of the most serious environmental issues is air pollution. Unlike other environmental concerns, this form of pollution is extremely challenging to regulate. The greenery of roadside trees plays a significant role in air purification and pollutant absorption, therefore helping to mitigate environmental pollution. Several plants can absorb and store toxins in their leaves from the atmosphere. Green plants have the potential to work as sinks and filters for air pollutants. Green belt development along national highways is a cost-effective and environmentally sustainable method of reducing air pollution. Sensitive and tolerant plants against air pollution can be identified by evaluating their air pollution tolerance index (APTI) and anticipated performance index (API) values. In this study, the susceptibility level of plant species to air pollution was assessed using APTI and API. The four parameters on which APTI depends are ascorbic acid content, total chlorophyll content, relative water content, and leaf extract pH. For the estimation of API, the plant's biological and socioeconomic factors like tree habit, canopy structure, type, size, texture, and hardness of the plant are also assessed. These parameters were determined and incorporated into a formula that represents the APTI and API of plants. Moreover, multilinear regression modeling was performed using a Statistical Package for the Social Sciences (SPSS, V25) and found that pH and ascorbic acid content in plant leaves have a significant role in the calculation of APTI and tolerance potential of plants. Therefore, APTI was assessed with seventeen plant species that are abundant in the area along the national highway in Kanpur, Uttar Pradesh, from Jan to Mar 2020. The APTI showed that Saraca asoca was the most resistant to air pollution, whereas Vachellia nilotica was the most sensitive. In addition, plants with higher APTI can also be used to reduce air pollution, while plants with lower APTI can be utilized to monitor air pollution. Based on the calculated API score, it is found that Ficus elastica (% score > 90) is the best option for green belt development. Urban local body (ULB) can also adopt Ficus religiosa, Saraca asoca, and Aucuba japonica (having % a grade score of 80-90) for mitigation of air pollution. The study indicates that plantations of tolerant species are useful for biomonitoring and developing green belts on and along national highways.

Impact of air pollution and leaf dust deposition on biochemical parameters and air pollution tolerance index (APTI) of some road side plants

Plants growing in cities and near major roads absorb the pollutants and dust particles at their foliar surface. Biochemical parameters like leaf pH, relative water content, total chlorophyll content are used for analyzing impact of dust deposition on plant leaves and Air Pollution Tolerance Index (APTI). In the present study, leaf samples of different plant species like, Tamarindus indica Linn., Tectona grandis L.f, Vitex negundo L., Thevetia peruviana (Pers.) K. Schum., Tecoma stans(L) Juss. ex Kunth, Nerium oleander L., Ficus.sp L, Muntingia calabura L., Ricinus communis L., Erythrostemon gilliesii (Hook) Link &amp; al. were taken from road sides which has a heavy load of vehicles. Changes in biochemical parameters of plants were evaluated and determined Air Pollution Tolerance Index (APTI). Results has comparatively high APTI values. So, these plants can be used for plantation on the road sides as pollution scavengers. Keywords: dust particles, plantation, pollution scavengers, air pollution tolerance index

Evaluation of the Air Pollution Tolerance Index of 12 Plant Species Growing in Environments with Different Air Pollution Levels

Background and objective Particulate matter (PM) is the most dangerous form of air pollution, and causes many diseases. Plants act as bio-filters to help reduce PM in the atmosphere. PM also influences the growth of plants, so selecting suitable plant species for specific environmental conditions is very important. The air pollution tolerance index (APTI) was used to determine the tolerance level of each plant species to air pollution. The purpose of this study was to determine the tolerance to air pollution of various plant species in order to identify plant species that can be grown in polluted environments; this was achieved by evaluating the APTI of plants. This study analyzed the biochemical parameters of 12 plant species at two sites with different air pollution levels (urban forest and roadside) to assess and compare the APTI of plant species. Methods The healthy leaves of 12 plant species (6 broad leaves and 6 needle leaves) that are commonly used in landscapes in Korea were chosen for this study. The same plant species were collected from two sites with different pollution levels and were analyzed immediately; one site was an urban forest (Chungcheongbuk-do Forest Environment Research Institute) with an area of 25 ha and featuring high vegetation coverage, while the other was at a high-traffic roadside next to a crossroads near the Cheongju Express Bus Terminal. We used the leaf samples to analyze four biochemical parameters of each plant: leaf extract pH (pH), relative leaf water content (RWC), total chlorophyll (TChl), and ascorbic acid. Finally, based on these values, APTI values were calculated. Results The APTI values were different between all 12 plant species at both sites with different levels of pollution. APTI had a significant correlation with the biochemical parameters of plants. Plants in the urban forest and at the roadside showed APTI values ranging from 6.89–9.37 and 7.57–9.94, respectively. The APTI of the roadside plant species tended to be higher than that of the plants from the urban forest. Among 12 plant species, Acer palmatum, Acer buergerianum, and Pinus densiflora had high APTI values. These plant species can serve as biofilters in environments with high air pollution. Conclusion The APTI of the 12 plant species in this study can aid in the selection of suitable plant species from environments with different levels of air pollution. The high APTI of some roadside plant species may show their tolerance under environmental pollution-related stress, or demonstrate their adaptability to the polluted environment. In the future, we need to examine more plant species under various environmental conditions to understand their tolerance levels to air pollution and to correlate plants with air pollution. Further, more studies on other air pollutants that can influence plant growth, such as SO2 and NOx, should be conducted.

Impact of vehicular emissions on anatomical and morphological characteristics of vascular plants: A comparative study

Abbottabad is a famous tourist destination due to its greenery and location. However, rapid increase in population and unplanned urbanization cause various environmental problems. Among different environmental stress, vehicular emission is the major issue for the survival and sustainability of plant species. This study aimed to investigate the effects of atmospheric pollution (caused by vehicular emission) on the anatomical, biochemical and morphological aspects of plant species present alongside the roads of Abbottabad, Pakistan. The plants were also collected from control sites (away from road-sites) for comparison. The results showed that various morphological characteristics of plant species including petiole length, vein-to-vein difference between leaves and length to breadth ratio of leaves were adversely affected by air pollution. The stomatal index varies in plant species because of variations in the numbers of epidermal cells. The air pollution tolerance index (APTI) of plant leaves from contaminated areas was reported to be higher as compared to control (non-contaminated) areas. Consequently, the findings from this study confirmed that plant species growing alongside of Abbottabad roads has greater tolerance than plant species growing in solitude areas away from road sites (control sites). Among different studied plants, Juglans regia, Morus nigra, Xanthium strumarium, Prunus armenica, Diospterus lotus and Populus ciliata have highest APTI and found to be more suitable for plantation in Abbottabad.

Evaluation of air pollution tolerance index (APTI) of plants growing alongside inner ring road of Kathmandu, Nepal

ABSTRACT The air quality of the Kathmandu valley is highly degraded by pollution from motor vehicles. Planting green vegetation along roadsides has been shown to reduce air pollutants. Different leaf parameters like pH, relative water content, chlorophyll content, and ascorbic acid content, that comprise the Air pollution tolerance index (APTI), were used to test the susceptibility of plants to air pollution. APTI values of ≤11, 12–16, and ≥17 categorised the plant species under sensitive, moderate, and tolerant species, respectively. In the present study, all the plant species had APTI less than 11. The highest APTI value was for Mangifera indica (10.62) and the lowest for Buddleia asiatica (6.92). Therefore, based on the findings of the present study, planting trees with high APTI value alongside the roads may help reduce air pollution as these trees are resistant to high pollution levels.

Some roadside medicinal weeds as bio-indicator of air pollution in Kolkata

Air pollution is a significant matter of concern in today’s world. The current study objective is to determine the air pollution tolerance index (APTI) of Kolkata from five roadside medicinal plants, namely, Heliotropium indicum, Tridax procumbens, Cleome rutidosperma, Commelina benghalensis, and Euphorbia hirta. APTI was determined by fresh leaves extracts using four important plants physiological parameters such as relative water content, ascorbic acid (AA) content, total chlorophyll (Chl) content, and pH of leaf extracts. Three sites or areas were selected for the study in Kolkata. It includes a control area (Jadavpur), a moderately polluted area (Salt Lake, Sec V), and highly polluted area (Dunlop Bridge) based on the West Bengal State Pollution Control Board databases and previous study reports. For estimating Chl and AA content spectrophotometer and titration method were used, respectively. A higher APTI value was found in plants located at the control area and moderately polluted area. However, the lower amount of APTI value was found in plants located in the polluted area. The study concludes that air pollution has a severe impact on plant and human health. The plant species with high APTI value can be planted around industrial complexes, roadsides, and urbanized sites to monitor air pollution in greener and cost-effective way.

Variation of tree biochemical and physiological characters under different air pollution stresses.

The present work was undertaken in order to detect some pollution responsive variables such as ascorbic acid, pH, total chlorophyll, relative water content, total soluble sugar, amino acid and protein of four selected plant species, namely Ficus religiosa, Anthocephalus cadamba, Lagerstroemia speciosa and Cassia siamea, at nine different sites of Durgapur, West Bengal, India. The spatial variability analyses of Air Pollution Tolerance Index (APTI) along with Anticipated Performance Index (API) were also examined on each plant species. In this study, the highest APTI was recorded in L. speciosa (183.54mg/g) during 2015 at site S5 (CCR), whereas the lowest APTI was reported in C. siamea (11.25mg/g) during 2014 at site S3 (DGC). The API gradation revealed that L. speciosa was categorised as a best performer followed by A. cadamba and F. religiosa; in contrast, C. siamea showed poor performance among all the sites. One-way ANOVA (at p < 0.05, with Dunnett's post hoc) was conducted for spatial variability analysis both on biochemical parameters and air pollutants (SO2, NOx and SPM) with respect to control site, while two-way ANOVA also operated for the detection of spatio-temporal interaction on concerned biochemical parameters of each tree species. A significant positive correlation was observed both in ascorbic acid and APTI of A. cadamba and L. speciosa with the air pollutants. So it would be said that, for varied environmental situations, different biochemical responses have been reflected by vegetation of the same species. Thus, the present study has tremendous potentiality to screening out tree species on the basis of APTI with pooling their API assessment category and spatial variability detection of biochemical parameters. Biochemical plasticity and adaptability were better revealed on L. speciosa, F. religiosa and A. cadamba which will be suitable for green belt development in air pollution-affected areas.

Assessment of Air Pollution Tolerance Index (APTI) and Anticipated Performance Index (API) of Roadside Plants for the Development of Greenbelt in Urban Area of Bathinda City, Punjab, India.

The aim of the present study is to biomonitor the tolerance level of roadside plant species towards mitigation of air pollution for the development of greenbelt. The leaves of four plant species (Azadirachta indica, Ficus benghalensis, Melia azedarach and Polyalthia longifolia) were collected from 41 sampling sites of Bathinda city during summer and winter seasons. Seasonal variation in APTI and API was determined in selected plants. Highest APTI (13.54) was reported in F. benghalensis during summer and lowest APTI (11.69) in A. indica during winter season. The APTI and API value revealed that F. benghalensis was the best performer, A. indica and M. azedarach were excellent performers and P. longifolia a good performer in greenbelt development to mitigate the air pollution. Pearson's correlation analysis illustrated significant correlation between APTI, ascorbic acid, total chlorophyll, relative water and pH, respectively.

Assessment of anticipated performance index of some deciduous plant species under dust air pollution.

Green vegetation improvement is an economical strategy to mitigate dust air pollution. The anticipated performance index (API) is considered a main criterion to select the suitable plants of urban forests. API is calculated by taking air pollution tolerance index (APTI) and socio-economic and biological aspects into account. In the present work, API of four current deciduous tree species in urban areas of Iran was evaluated. The seedlings were soil-dusted by a dust simulator in plastic chambers at levels of 0, 300, 750, and 1500μg/m3 at intervals of 1week for 70days. At 750 and 1500μg/m3 dust concentrations (DCs), greatest dust collection capacity was observed with Morus alba and the lowest one with Melia azedarach. Increasing DC declined APTI of all species. At 750μg/m3 DC, only Morus was tolerant, but at 1500μg/m3 DC, this species and Melia were categorized as intermediate, and Celtis caucasica and Fraxinus rotundifolia as sensitive. Morus was assessed as a good performer under two higher DC. Celtis was recognized as a moderate under 750μg/m3 DC and poor performer under 1500μg/m3 DC. Thus, Celtis can be considered as a biomonitor for air quality or as sink for dust in high dusty areas because of its high capacity of dust deposition. At two higher DCs, Fraxinus and Melia showed very poor and poor performance; planting these species in high dust areas is not recommended. In contrast, Morus is the most suitable tree species for urban green spaces in dusty regions, due to its high dust collection capacity and high APTI and API values.